A wide range of chemicals are applied to plants to encourage growth, discourage growth, and/or discourage pests. Many of these chemicals are active by contact with plant leaves. Usually, contact for some minimum amount of time is necessary for full activity. Sticker adjuvants are widely used to slow or prevent the active ingredient from washing off the plant surface during rain or irrigation.
Older, simpler sticker adjuvants used included fatty acids and their salts, mineral oils and drying oils (such as tung oil and linseed oil). More recent sticker adjuvants include latex polymers, polymeric terpenes, alkylphenol alkoxylates (such as nonylphenol ethoxylate condensate polymers), fatty acid derivatives, gums and polysaccharides.
However, these currently used sticker adjuvants have limited formulation abilities and the alkylphenol alkoxylates, such as the popular sticker adjuvant is based on nonylphenol ethoxylate condensate polymers, have been restricted in the various regions.